If you get some errors in compiling Android 4.0 on Ubuntu 11.10 x86 apply the following patch, accordingly to what I've found at this link:
http://e-xiao.blogspot.com/2011/10/r...droid-234.html
"It will patch line 61 in core/combo/HOST_linux-x86.mk as following.
-HOST_GLOBAL_CFLAGS += -D_FORTIFY_SOURCE=0
+HOST_GLOBAL_CFLAGS += -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=0"